RESTORATION OF MARSH VEGETATION IMPACTED BY THE AMOCO CADIZ OIL 

 SPILL AND SUBSEQUENT CLEANUP OPERATIONS AT ILE GRANDE, FRANCE 



Ernest D. Seneca and Stephen W. Broome' 



INTRODUCTION 



General 



Tidal salt marshes functon to stabilize estuarine shorelines, to 

 exchange nutrients with sediments and the surrounding waters, to 

 provide energy as detrital material to the estuarine food web, and to 

 serve as nursery grounds for many commercially important fish and 

 shellfish. Because competing land uses have resulted in a decrease in 

 areal extent of these valuable resources in the past, there have been 

 concerted efforts recently to preserve the remaining marshlands and to 

 reestablish marshes at selected sites. Techniques and procedures have 

 been developed to: (1) reestablish marsh in areas where Man has 

 destroyed natural marsh, (2) reestablish marsh along shorelines where 

 storms have damaged or destroyed natural marsh, (3) establish marsh 

 along canal banks and shorelines to stabilize the substrate and retard 

 erosion, and (4) establish marsh on dredged material (Woodhouse et al., 

 1974; Garbisch et al., 1975; Seneca et al., 1976). 



Our research efforts in marsh establishment along the southeastern 

 coast of the United States led us to respond to an invitation from the 

 joint scientific commission of the National Oceanic and Atmospheric 

 Administration (NOAA)/Centre National pour l'Exploration des Oceans to 

 study the effects of the Amoco Cadiz oil spill. We developed a 

 proposal for restoring marsh at the lie Grande site adapting techniques 

 and procedures developed for Spartina alternif lora Loisel. in North 

 Carolina (Woodhouse et al . , 1974; Seneca et al., 1976) to restoration 

 of a part of the lie Grande marsh using vegetation indigenous to that 

 region. This interim report contains results from 2 years' marsh 

 rehabilitation research at lie Grande and a nearby estuary at Kerlavos. 



Literature Review 



The effects of oil pollution on salt marsh vegetation have been 

 studied and reported by European researchers. Based on observations of 

 Welsh salt marshes affected by oil spills from the Chryssi P. 

 Goulandris in January 1967 and the Torrey Canyon in March 1967, Cowell 

 (1969) rated susceptibility of marsh plants to crude oil and concluded 

 that salt marshes dominated by Spartina townsendii H. and J. Groves and 

 Puccinellia maritima (Huds.) Pari, were most subject to damage. 

 Stebbings (1970) studied the effects of oil from the Torrey Canyon 

 spill on salt marshes in Brittany and found that these marshes were 



1 ) Department of Botany and Department of Soil Science, respectively 

 North Carolina State University, Raleigh, North Carolina U.S.A. 27650 



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